Apparatus for preparing a microelement for soldering

ABSTRACT

Apparatus for preparing the conductors projecting from a flatpack for soldering comprises an anvil supporting the conductors and a soldering wire transversely of the conductors, a reciprocable plunger mounted above the anvil for exerting a predetermined pressure against a soldering wire placed transversely over the conductors, and cooperating side walls of the plunger and the anvil forming a scissors for severing the soldering wire upon downward movement of the plunger.

United States Patent Anglade [451 Apr. 25, 1972 [54] APPARATUS FORPREPARING A [56] References Cited MICROELEMENT FOR SOLDERING UNITEDSTATES PATENTS [72] lnventor: Francis Anglade, Levallois-Perret, France3,051,026 8H962 Da Costa 228/6 [22] Filed: June 16, 1970 3,102,3319/1963 Da Costa... A l N 48 901 3,439,520 4/1969 Schwartz ..29/203 XPrimary ExaminerThomas l-l. Eager Related Application Dam Attorney-Lane,Aiken, Dunner & Ziems [63] Continuation of Ser. No. 760,146, Sept. 17,1968,

abandoned. ABSTRACT Apparatus for preparing the conductors projectingfrom a flat- 1 Foreign Application Dita pack for soldering comprises ananvil supporting the conduc- 29 1968 France 1 46510 tors and a solderingwire transversely of the conductors, a Mar 1968 France I 46511reciprocable plunger mounted above the anvil for exerting apredetermined pressure against a soldering wire placed transversely overthe conductors, and cooperating side walls of the if 5" "29/203 plungerand the anvil forming a scissors for severing the sol- E i i 228/6dering wire upon downward movement of the plunger.

10 Claims, 3 Drawing Figures PATENTEDAPR 2 5 I972 CRQMCIS QNGLADG $1 (0%KM Acew BACKGROUND AND SUMMARY OF THE INVENTION The present inventionrelates to soldering electronic microelements. It is concerned with anapparatus for preparing such micro-elements for soldering elements.

Various soldering procedures for electrical micro-elements have beenproposed but they depend either on the skill of the operator in a verytime-consuming manual operation, are quite wasteful in case ofoccasional failures, or are applicable only to certain structures.

In view of the shortcomings of such procedures and also because theelements to be soldered are very fragile and sensitive to hightemperatures, it is preferred to use electrically heated solderingirons. However, in this case, it is necessary to provide a sufficient,predetermined amount of solder upon which the soldering irons act toprovide a good mechanical and electrical connection between the solderedparts.

It is accordingly an object of the present invention to prepare anelectrical micro-element for soldering by a soldering iron with asufficient amount of uniformly distributed solder to assure such aconnection without raising the temperature of the soldering iron to adamaging degree.

It is another object of the invention to provide simple and effectiveapparatus for such preparation and for soldering the prepared element.

The above and other objects are accomplished in accordance with thisinvention with an electronic micro-element which comprises a pluralityof conductors projecting from the element in one direction and in asingle plane, and a soldering wire or rod including a core of fluxingmaterial extending across the conductors in a direction transverse tothe one direction, the wire or rod and the conductors forming amechanical bond at their respective points of intersection.

According to the invention, such an element is prepared by placing thespaced conductors, which are disposed in a single plane, with theconductors extending in one direction, on a flat support to maintainthem in this plane. A soldering wire or rod is delivered from a supplyacross the conductors in a direction transverse to the one direction,and the wire or rod is placed over the conductors. Pressure is thenapplied against the soldering wire or rod in a direction perpendicularto the plane until the wire or rod has been somewhat flattened and hasbeen pressed into the conductors whereby the wire or rod and theconductors form a mechanical bond at their respective points ofintersection. The wire or rod is severed from the supply while thepressure is applied thereagainst, then the pressure is lifted to leavethe soldering wire or rod connected to the conductors.

The apparatus for carrying out this method comprises an anvil memberhaving a flat upper surface supporting the spaced conductors in theirplane. A ledge at one end of the anvil member defines a groove extendingin a direction substantially transverse to the one direction and capableof receiving the soldering wire or rod. A plunger is mounted above theflat upper surface of the anvil member and is vertically reciprocable inrelation thereto, the plunger having a lower flat surface facing theupper surface of the anvil member and substantially parallel thereto.Means, for instance fluid pressure, is provided for exerting apredetermined downward pressure on the plunger against the solderingwire or rod placed transversely over the conductors through the groove,and cooperating side walls of the plunger and anvil member ledge form ascissors upon downward movement of the plunger for severing thesoldering wire or rod placed over the conductors through the groove.

BRIEF DESCRIPTION OF DRAWING The above and other objects, advantages andfeatures of the present invention will become more apparent by referenceto the following detailed description of a preferred embodiment thereof,taken in conjunction with the accompanying drawing wherein FIG. 1 is aperspective view of one end of a flat-pack from which project theelectrical connecting conductors to be so]- dered to a circuit;

FIG. 2 is a schematic perspective view of an apparatus of thisinvention; and

FIG. 3 is a view similar to that of FIG. 1, showing a soldering wireconnected with the conductors by means of the apparatus of FIG. 2.

DETAILED DESCRIPTION Referring first to FIG. 1, the element to besoldered is constituted by a sealed casing 101 enclosing a plurality ofelectronic micro-elements. A plurality of leads or electrical connectingconductors 103 project from lateral wall 102 of the casing, theconductors being arranged in one plane and leading from respectiveelectronic micro-elements sealed within the casing to be connected bysoldering to a printed circuit, for instance. The leads areequidistantly arranged, have been cut to a predetermined length, and arepolished to form a perfectly plane surface.

The manner of uniting a soldering wire or rod 107 with the conductors103 is shown in FIG. 2.

The casing 101 is placed with its lateral wall 102 adjacent an anvil 104so that its plane upper surface 110 supports the conductors 103. A ledge105 extends upwardly from the anvil at one side thereof, the ledgedefining a groove 106 arranged to receive the soldering wire or rod 107extending longitudinally of the anvil transversely across and above theplane surface of the conductors 103. A vertically movable plunger 108 ismounted above the anvil 104 and has a lower surface 111 cooperating withthe upper surface of the anvil when the plunger is depressed by means ofpiston rod 109 which may be fluid-pressure operated.

The two surfaces 110 and 111 are perfectly plane and parallel to eachother. In the illustrated embodiment, plunger surface 111 defines ashallow, longitudinally extending recess 112 arranged to engage thesoldering rod or wire 107 and thus to limit the flattening thereof whenthe plunger is move against the anvil. Provision of such a recess is notessential, however, and could be replaced, for instance, by a suitablyarranged limiting stop to limit the maximal downward movement of theplunger.

As will be obvious from a consideration of FIG. 2, the end wall B of theplunger will cooperate with the insidewall B of anvil ledge 105 toprovide a scissors for severing the soldering rod or wire 107 while itis flattened and. set on he conductors 103.

The operation of the apparatus of FIG. 2 for making the element 101ready for soldering in the manner shown in FIG. 3

will be obvious from the above description.

First, the casing 101 is placed adjacent the anvil 104 so that the sidewall 102 abuts one of the side walls of the anvil, and the conductors103, which lie in a perfect plane, are supported on surface 110 of theanvil. The soldering wire or rod 107 is then advanced from a source ofsupply (not shown) through the groove 106 of anvil ledge 105 until itsleading end extends beyond the outermost conductor 103 by apredetermined length designed to produce a good soldering union. Theplunger is now depressed under a predetermined pressure until it pressesagainst the soldering wire or rod and flattens the same while settingthe conductors in the soldering wire or rod in the manner shown in FIG.3. At the same time, the soldering wire or rod is severed by thecooperating action of walls B and B.

What is claimed is:

1. An apparatus for preparing one or more electrical leads forsoldering, said apparatus comprising a first forming member adapted tosupport said leads along with a supply of solder material in contactwith said leads, a second forming member normally disposed in spacedrelation to said first forming member, and means to press said formingmembers together to form a bond between said solder material and saidleads, one of said forming members having means for limiting theflattening of said solder material during the pressing together of saidforming members.

2. The apparatus of claim 1 wherein said solder material is in the formof a strip, and wherein said means for limiting the flattening of saidsolder material is in the form of a recess formed in said one formingmember and adapted to receive a portion of said strip, thecross-sectional area of said recess being less than that of said strip.

3. The apparatus of claim 1 wherein said solder material is in the formof a strip, and wherein said first forming member comprises means forpositioning said strip so that it extends in a generally transversedirection with respect to said leads.

4. The apparatus of claim 3 wherein said means for positioning saidstrip is in the form of a recess-defining means disposed adjacent thesupport surface of said first forming member.

5. The apparatus of claim 4 wherein said solder material is in the formof a continuous strip connected to a source of solder material, aportion of said second forming member being adapted to cooperate withsaid recess-defining means for severing said strip from said sourceduring said pressing together of said fonning members.

6. The apparatus of claim 1 wherein said solder material is in the formof a continuous strip connected to a source of solder material, andfurther comprising cooperating means on said forming members forsevering said strip from said source during said pressing together ofsaid forming members.

7. An apparatus for preparing one or more electrical leads forsoldering, said apparatus comprising a first forming member adapted tosupport said leads along with a strip of solder material connected to asupply thereof, a second forming member normally disposed in spacedrelation to said first forming member, means to press together saidforming members to form a bond between said solder material and saidleads, and cooperating means formed on said forming members for severingsaid strip from said supply during the pressing together of said formingmembers.

8. The apparatus of claim 7 wherein said first forming I membercomprises means for positioning said strip of solder material so that itextends in a generally transverse direction with respect to said leads.

9. An apparatus for preparing for soldering a plurality of spacedconductors projecting from an electronic micro-element in one directionand in one plane, comprising 1. an anvil member having a flat uppersurface supporting the spaced conductors in said plane,

a. a ledge at one end of the anvil member defining: groove extending ina direction substantially transverse to the one direction and capable ofreceiving a soldering wire or rod;

2. a plunger mounted above the flat upper surface of the anvil memberand vertically reciprocable in relation thereto,

b. the plunger having a lower flat surface facing the upper surface ofthe anvil member and substantially parallel thereto;

3. means for exerting a predetermined downward pressure on the .plungeragainst a soldering wire or rod placed transversely over the conductorsthrough said groove; and

4. cooperating side walls of the plunger and of the anvil member ledgeforming a scissors upon downward movement of the plunger for severingthe soldering wire or rod placed over the conductors through the groove.

10. The apparatus of claim 9 wherein the lower surface of the plungerdefines a shallow groove extending in said transverse direction inalignment with said groove, the depth of the groove being less than thediameter of the soldering wire or rod.

1. An apparatus for preparing one or more electrical leads forsoldering, said apparatus comprising a first forming member adapted tosupport said leads along with a supply of solder material in contactwith said leads, a second forming member normally disposed in spacedrelation to said first forming member, and means to press said formingmembers together to form a bond between said solder material and saidleads, one of said forming members having means for limiting theflattening of said solder material during the pressing together of saidforming members.
 2. The apparatus of claim 1 wherein said soldermaterial is in the form of a strip, and wherein said means for limitingthe flattening of said solder material is in the form of a recess formedin said one forming member and adapted to receive a portion of saidstrip, the cross-sectional area of said recess being less than that ofsaid strip.
 2. a plunger mounted above the flat upper surface of theanvil member and vertically reciprocable in relation thereto, b. theplunger having a lower flat surface facing the upper surface of theanvil member and substantially parAllel thereto;
 3. means for exerting apredetermined downward pressure on the plunger against a soldering wireor rod placed transversely over the conductors through said groove; and3. The apparatus of claim 1 wherein said solder material is in the formof a strip, and wherein said first forming member comprises means forpositioning said strip so that it extends in a generally transversedirection with respect to said leads.
 4. The apparatus of claim 3wherein said means for positioning said strip is in the form of arecess-defining means disposed adjacent the support surface of saidfirst forming member.
 4. cooperating side walls of the plunger and ofthe anvil member ledge forming a scissors upon downward movement of theplunger for severing the soldering wire or rod placed over theconductors through the groove.
 5. The apparatus of claim 4 wherein saidsolder material is in the form of a continuous strip connected to asource of solder material, a portion of said second forming member beingadapted to cooperate with said recess-defining means for severing saidstrip from said source during said pressing together of said formingmembers.
 6. The apparatus of claim 1 wherein said solder material is inthe form of a continuous strip connected to a source of solder material,and further comprising cooperating means on said forming members forsevering said strip from said source during said pressing together ofsaid forming members.
 7. An apparatus for preparing one or moreelectrical leads for soldering, said apparatus comprising a firstforming member adapted to support said leads along with a strip ofsolder material connected to a supply thereof, a second forming membernormally disposed in spaced relation to said first forming member, meansto press together said forming members to form a bond between saidsolder material and said leads, and cooperating means formed on saidforming members for severing said strip from said supply during thepressing together of said forming members.
 8. The apparatus of claim 7wherein said first forming member comprises means for positioning saidstrip of solder material so that it extends in a generally transversedirection with respect to said leads.
 9. An apparatus for preparing forsoldering a plurality of spaced conductors projecting from an electronicmicro-element in one direction and in one plane, comprising
 10. Theapparatus of claim 9 wherein the lower surface of the plunger defines ashallow groove extending in said transverse direction in alignment withsaid groove, the depth of the groove being less than the diameter of thesoldering wire or rod.